I think my kitchen faucet has been incorrectly installed. It'll run full hot and full cold but is very touchy to try and get a mix of hot and cold. (System is equal low pressure)

I'm wondering if it could need a backflow restrictor.

I'm only guessing this because I installed the bathroom faucet myself and the kit included a restrictor. It mixes without problems.

Am I right in this assumption? If so, which line does the restrictor go in?

Thanks :-)